Uses your Hide and Move Silently skills to adopt a sneaking stance and avoid detection. Enemies with a Spot and Listen below your Hide and Move Silently skills will not notice you. The longer you stay near an enemy, the larger their bonus to spot you. Using certain objects, such as doors and levers, or being hit will knock you out of the stance.
Update 19 has revised the entire stealth system for players and attackers.
Update 73 Patch 1 revised the way monsters search for sneaking players.
Player Movement and Class/Epic Destiny Changes
Jumping and tumbling while in stealth is now possible, at a −20 penalty to Jump and Tumble skills. If any of these skills are brought to negative scores while in Sneak, they are disabled for the player.
More class enhancement trees offer Faster Sneaking to aid in avoiding being spotted.
With these Update 19 changes, abilities of the Shadowdancer epic destiny and the Ranger class were revised.
Shadow Training II (innate ability which formerly gave temporary jumping): Activate: For 30 seconds, while sneaking you gain: Full movement speed, +5 Attack bonus to-hit with Sneak Attacks, +2 Sneak Attack dice, +3 Hide, +3 Move Silently.
Hide in Plain Sight (Ranger Feat): You are a master when it comes to hiding in places others think impossible. You gain +1 Hide and +1 Move Silently for every three seconds you stand still, up to +5. While you are sneaking and standing still (for 3 seconds), enemies don't gain Spot bonuses until they get much closer to you, and the bonuses are smaller.
All Sneak Speed enhancements are now on the Enhancement channel, and therefore will not stack. We've also fixed the Antirequisite flags on these abilities to more reliably prevent players from taking more than one.
Shadow Training II in Shadowdancer now gives a 150% Enhancement bonus to Stealth Movement Speed instead of setting you to the normal base movement.
The more eyes they get, larger the bonus they receive to Spot you.
The Hide skill works against the enemy's Spot check. The higher the Hide, the less likely you will be immediately detected as you get closer to an enemy. However, the new system makes the enemies far more vigilant.
When a stealthed player enters a line-of-sight of the enemy, the Spot check instantly begins. The player will see a series of flashing Spot detection symbols above an enemy's head, changing in color up to three states of eye symbols as the enemy's Spot bonuses increase. The closer the player or the weaker their Hide skill, the more active the "pinging", until the player moves out of the enemy's visual arc or until the enemy's Spot exceeds the player's Hide skill, and has detected the player. The further away the player, the less likely that the Spot condition may change or activate.
Prior to Update 19, the player might see one to three "eye" symbols over their character. In the new system, you'll see only a single eye over your character only when you are in line-of-sight of an enemy (their Spot check is active). If you have an eye over your character while in stealth, you should note quickly how far you are from an enemy (they could be approaching and also hidden), taking cover immediately if required to escape detection.
Monster sight detection of stealthed players has been decreased by 28% (was 25 meters, now 18) if their Stealth score exceeds the monster's spot skill. This includes bosses and monsters that can see normally through stealth (All-Seeing).
When the player is Stealthed, they now see a visual purple eye VFX over any monster that pierces Stealth (All-Seeing and All-Hearing/Tremorsense).
Hearing range on "All-Hearing" monsters (aka monsters with Tremorsense) has been reduced by 10% (from 20 meters down to 18).
The Move Silently skill works as before, against the enemy's Listen check. The sensitivity of this check is greater. Breaking objects, the sounds of summoned creatures, or footfalls will instantly get the attention of enemies who are nearby. Enemies who hear something will show a large red question mark over their heads and immediately go to investigate the sound. Using levers, switches and opening doors generally do not make sounds in terms of stealth gameplay.
Red footfalls on a player indicate that something has sensed and is tracking you audibly. This is typical when spiders detect you, using tremor-sense, and oozes. The deeper and redder the red footfalls, the more enemies have found and can hear you.
White footfalls suggest that an enemy is nearby and may soon hear your approach (your Move Silently score is failing).
Enemy Detection, Movement and Player Escape
When a red question mark appears over their head, they have heard something and are going to investigate.
As stated, an enemy's Spot and Listen check is always active.
Enemies walk or run realistically to something suspicious and do not "slide" to you if detected as before Update 19.
An enemy that knows your position while stealthed will show a large red eye over their head. They might have targeted you by sound or sight.
If a player is detected, it is now possible to escape from a pursuer if the player can
Place sufficient distance between themselves and the enemy to break their ability to hear them, and
Break the line-of-sight to the enemy (going around a corner, for instance) and
Successfully go into Sneak or become invisible and remain motionless until the enemy passes.
Even an enemy with a red-eye might not know your precise location but will home in quickly to where you were initially found. If you are still stealthed and invisible, you may still be able to get away if you can sneak fast enough out of the enemy's Spot and Listen range. If you can do so, the enemy will still search for a time, but blindly.
Enemies that are moving and searching for you, while often attacking blindly to fish you out, don't get bonuses to Spot or Listen while in pursuit.
A stealthy player can move away from searching enemies with a good Move Silently skill.
After a time, the enemies will stop their search. Depending on the AI, they may return to their original location or remain in place where they halted the search.
If an enemy hears or sees something new, they will resume their search. If they aren't moving, the enemy regains their Spot bonuses.
Invisibility
Invisibility works truly as being immune to Spot unless you are too close to the enemy (within 2 meters, or a human player's body length). When invisibility is broken, the enemy may instantly spot you if they are facing you.
Invisibility does not make a player soundless. A non-stealthy player has a Move Silently score of 0. If enemies hear footfalls, they will investigate, and will find a loud, invisible player once close enough to see them. Sounds from any summons (even if they seem to float), breakables or levers could also attract enemies to invisible players.
Invisibility guards that activate while at close range may not help if you were already within 2 meters of the enemy and are likely moving loud enough for enemies to hear you at such close proximity.
Pale Masters in Wraith/Shadow forms and Shadowdancers in Shadow Form, while they appear to float, still make footfalls for the purposes of detection.
Limitations
A red eye indicates that the enemy found you.
Stealth cannot work against enemies with
Tremor-sense (Spiders, in general: You will see red detection eyes and red footfalls on your player once close enough to any spider.)
While stealth still works well against beholders, the monster's 360-degree Spot search with the bonus (being a giant, multi-eyed ball) means that a stealthy player has to move faster than before to attack.
Again, any enemy is likely to detect you with stealth, invisibility or both if you are closer to 2 meters (one body length) from the enemy, aren't silent, or within the enemy's visual line-of-sight.
Tips
While Bard, Ranger, Monk and Rogue classes have Hide and Move Silently as class skills, it is not impossible to add additional stealth to many classes with some limits.
Wear light armor or no armor. Medium and Heavy Armor increase your Armor Check Penalty, reducing your effectiveness in stealth, Jump, Swim and Tumble.
Equip stealth-granting items such as the Cloak of Shadows to add Competence bonuses to your Hide and Move Silently skill.
Invisibility is immunity to Spot as long as you keep greater than 2 meters from a target, and provided they do not have True Seeing or See Invisibility. Invisibility does not make you silent. If you are adding cross-class points, add to Move Silently first if you can make yourself invisible.
Add more points to Jump if you sneak regularly as you have a −20 penalty while sneaking. While a score of 40 or more gives no advantages to any character while not stealthed, the extra points make the difference while sneaking. Enhancements and Competence bonus items can aid here.
Have a Ranger in your party. They can cast Camouflage, a +10 Determination bonus to Hide that stacks with other bonuses. They also can cast Pass Without Trace, a stacking +5 Enhancement bonus to Move Silently if you're wearing items with Competence bonuses.
The following creatures have been confirmed to be capable of sneaking (there might be more – research continues – be on your guard). To detect these enemies faster and farther away, increase your own Spot skill with action points, feats, enhancements and items. It's often beneficial to wear your high-Spot items while in Sneak.
